When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
It would help us help you if we knew the year of your truck, what engine you have, how many miles, any major mods, anything you have changed recently, and anything you have done to diagnose and or repair the problem.
From that much information I can only say you have either a bad Computer or a bad PIP sensor or a bad ICM or wiring or a bad ground or the distributor is not turning.
In other words the computer is either bad or it is not seeing the PIP train or it it is not grounded or it has open wires.